JPH0610608Y2 - Ion flow extraction electrode - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an ion flow extraction electrode in an ion beam processing apparatus.

[Prior Art] The ion beam processing method was developed to increase the degree of integration of an integrated circuit. It is widely used for forming a pattern of an integrated circuit by using ions extracted from an ion source. Since the action is the processing principle, it enables the formation of fine patterns.

Conventionally, as an ion beam processing apparatus that realizes this ion beam processing method, a method has been adopted in which plasma generated in a plasma generation chamber is electrostatically extracted by an ion flow extraction electrode to form an ion flow.

FIG. 1 is a schematic sectional view showing the structure of such an ion beam processing apparatus. In the figure, (1) is a plasma generation chamber, (2) is an ion flow extraction electrode, (3) is a processing chamber, and (4) ) Is the cathode, (5) is the seal wall, (6) is the anode, (7) is the electromagnet, and (1
0), (11), and (12) are power sources, (13) is an electrode, (14) is a sample, (15) is a mask, (16) is an exhaust port, and (17) is an air supply port.

The ion beam processing device is roughly divided into a plasma generation chamber (1) for generating plasma, an ion flow extraction electrode (2) for extracting the generated plasma as an ion beam, and a sample.
It is composed of a processing chamber (3) for irradiating the ion beam (14).

Further, the ion flow extraction electrode (2), so-called single-sheet type electrode is used, its structure is the insulator (21) on the plasma generation chamber (1) side, the conductor (22) on the processing chamber (3) side, It is composed of an integral grid having a large number of small holes (23) formed by penetrating the insulator (21) and the conductor (22).

Next, the operation of the conventional ion beam processing apparatus will be described. The inside of the seal wall (5) is evacuated to about 10 ⁻⁶ to 10 ⁻⁷ Torr, and an ionized substance such as Ar (argon) gas is introduced from the air supply port (17). Electrons emitted from the cathode (4) enter the anode (6) while performing cyclotron motion by the magnetic field created by the electromagnet (7). At that time, it is accelerated by the power source (10) and collides with Ar atoms to ionize Ar + ions and generate plasma. An ion sheath is formed near the plasma generation chamber (1) side surface of the ion flow extraction electrode (2) due to the influence of the electric field due to the space charge of the generated ions, and the ions ejected by thermal motion from this are generated by the power supply (11). The sample (14) is accelerated as a voltage and is irradiated as an ion shower through the ion flow extraction electrode (2) and the grid hole. The power supply (12) provides a voltage for preventing backflow of electrons from the processing chamber (3).

In addition, as the above-mentioned one-piece type electrode, one in which a conductor layer that constitutes an acceleration electrode is vapor-deposited on an insulating substrate is used, but what realized this is that a glass ceramic plate is formed with many small holes by etching. However, there was only a conductor which was coated with chromium on one side by vacuum evaporation.

[Problems to be Solved by the Invention] In the conventional single-plate type electrode as described above, a large number of small holes are formed in a glass ceramic plate by etching, and one surface of the plate is coated with chromium by vacuum vapor deposition to form a conductor. It is weak against heat and mechanical impact, and the performance as an electrode varies due to the thickness of the coated chrome, the amount of chrome entering the holes and its distribution, making it more expensive. there were.

The present invention has been made in order to solve such a problem, and an object thereof is to provide an ion flow extraction electrode that is inexpensive and has high quality stability.

[Means for Solving the Problems] As the ion current extraction electrode according to the present invention, an aluminum plate having a large number of holes perpendicular to the plate thickness direction, which is commercially available as a punching board, is used which is anodized on one side. I decided.

[Operation] In this invention, the punching board that is already on the market is used as the material, and the single electrode plate is formed only by subjecting it to the alumite processing. Therefore, the glass ceramic is not used and aluminum is used as the base material. It is resistant to heat and mechanical shock, and because it is not coated with chromium by vacuum deposition, there is little variation in performance, and etching is not required, so it is cheaper.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings. Second
FIG. 3 and FIG. 3 are views showing the structure of an ion flow extraction electrode according to the present invention. FIG. 2 (a) is a plan view, FIG. 2 (b) is a sectional view, and FIG. 2 (a) is an enlarged view of a portion indicated by A, and FIG. 3 (b) is an enlarged sectional view of a small hole portion. In these figures, (21) shows an insulator, but in this invention, it is composed of an oxide film (alumite). Reference numeral (22) indicates a conductor, which is made of aluminum in this invention. (23) is a small hole, and (24) is a mounting hole.

The ion current extraction electrode according to the present invention has a structure as shown in FIGS. 2 and 3, and the conductor (22) is an aluminum plate having a large number of holes perpendicular to the plate thickness direction which is already commercially available as a punching board. The plate is cut into a predetermined shape and used as is. Therefore, it is not necessary to purposely make a hole by etching as in the conventional case.

Further, since the insulator (21) can be configured by anodizing the one side of the punching board made of aluminum to form an oxide film, it is not necessary to configure the glass ceramic plate as in the conventional case, and the cost can be reduced. Since aluminum has high mechanical strength and aluminum has high thermal conductivity, cooling the outside can prevent thermal deformation, and a grid strong against sputtering and the like can be obtained.

If the surface of the conductor (22) made of aluminum is plated with nickel or the like, corrosion due to gas can be prevented and durability can be improved.

[Effects of the Invention] As described above, the present invention uses a punching board that is already on the market as a material, and a single electrode plate is formed only by subjecting it to alumite processing. Since it is used as a base material, it is resistant to heat and mechanical shock, and since it is not coated with chromium by vacuum deposition, there is little variation in performance, and since etching is not required, there are effects such as cost reduction.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing the structure of an ion beam processing apparatus, and FIGS. 2 and 3 are views showing the structure of an ion flow extraction electrode according to the present invention. (1) is the plasma generation chamber, (2) is the ion flow extraction electrode,
(3) is a processing chamber, (21) is an insulator, (22) is a conductor, and (23) is a small hole. The same reference numerals in the drawings indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] 1. An ion flow extraction electrode for forming an electric field for extracting ions generated in a plasma generation chamber for generating plasma into an machining chamber as an ion beam, wherein the ion flow extraction electrode is in a direction perpendicular to a plate surface. An ion current extraction electrode, characterized in that an aluminum plate having a large number of small holes is used as a material, and an oxide film formed by alumite processing is formed on one surface of the aluminum plate.